Adjustable eccentric



June 7, 1927. BUFFARD, 1,631,466

ADJUSTABLE ECCENTRIC Filed Sept. 24. 1924 3 Sheets-Sheet 1 p mmvrox. 8Y7M ATTORNEYS.

' 1,631,466 June 7, 1927. P. BUFFARDI ADJUSTABLE ECCENTRIC I Filed 24,1924 2 Sheets-Sheet 2 p INVENTOR. 7 BY; z 1/ W ATTORNEYS.

Patented June 7, 1927.

UNITED STATES PATENT OFFICE.

PASQUALE BUFFARDI, OF IRVINGTON, NEW JERSEY, ASSIGNOR T0 EDMUND W. ZEH,

OF NEWARK, NEW JERSEY.

ADJUSTABLE nooEN'raIo.

Application filed September 24, 1924. Serial No. 739,504.

The invention relates in general to eccentrics which are adjustable 'tovary the eccentricity for different purposes, for instance, to adjustthe stroke of the pitman or connecting rod of a press or other machinein which poweror motion is transmitted or applied through a rotatingshaft and pitman.

The objects of the invention are to provide an adjustable eccentricwhich can be used bet-ween spaced journals of a shaft without dividingsaid shaft transversely into separable sections; to enable such a shaftto be continuous or in one integral piece throughout said bearings andthe space between them; to thus retain unimpaired the strength anddurability of the shaft; to secure novel and improved features ofconstruction of an adjustable eccentric which will enable it to be usedon such a shaft; to arrange the adjustable parts outside the peripheryof the shaft; to provide the shaftcwith an cecentric portion whosecircumferential surface lies wholly outside the periphery of the shaft;to secure a construction which can be easily and quickly adjusted and inwhich the parts are positively held against working or wearing loosefrom adjusted relations, and to obtain other results and advantages asmay be brought out by the following description.

For the purpose of illustrating and describing the principles of myinvention and a preferred embodiment thereof, 1 have shown in theaccompanying drawings the in vention applied to a power press to adjustthe stroke of the pitman actuating a reciprocating die, but it should beunderstood that the invention is susceptible of other useswithoutdeparting from its spirit or scope.

Referring to said drawings in which the same characters of referencedesignate corresponding and like parts throughout the several views,

Figure 1 is a front elevation of a power press having an eccentricconstructed in accordance with the invention;

Figure 2 is an enlarged vertical longi tudinal sectional view throughthe eccentrio;

Figure 3 is a transverse vertical sectional View taken on the line 33 ofFigure 2; Figure 4 is a transverse vertical sectional view taken on theline H of Figure 2;

Figure 5 is a transverse vertical sectional view taken on theline 55 ofFigure 2;

Figure 6 is an end elevation of the shaft and the notched flange to holdthe eccentric bushing against rotation, and

Figure 7 is a detached end elevation of the eccentric bushing.

Specifically describing the present embodi ment of the invention thereference character'A designates the frame of a power press upon whichis journaled a drive shaft B carrying a drive pulley or wheel C, saidshaft being connected through the eccentric D embodying the inventionand the pitman E to a die carrying block, hammer or the like F, wherebyrotation of the shaftB causes reciprocation of the block F.

The shaft B is formed intermediate its ends with an integral eccentricportion 1 forming a crank, and an annular flange 2 at one end of saidcrank, which crank forms a body for the adjustable eccentric. The crank1 tapers or gradually decreases in diameter from said flange toward theother end which is screw-threaded at 3 to receive a nut or collar 4; andall points on the periphery of said crank are outside the peripheries ofthe ends of the shaft to permit the nut 4 to be slipped on from the endof the shaft.

An eccentric bushing or sleeve 5 is mounted and capable of rotation andlongitudinal movement upon said crank or body 1 between the flange 2 andthe nut 4c, the inner walls of said bushing being tapered to fit thecrank while the outer Walls are substantially cylindrical. Theeccentricity of the bushing 5 is complemental to that of the crank 1 sothat by rotating the bushing on the crank, the eccentricity of thebushing to the shaft B may be varied or adjusted.

F or holding the bushing 5 in adjusted position on the crank 1. theflange 2 is formed with a plurality of circumferentially spaced notches6, and the end of the bush ing 5 adjacent said flange is provided with alug or projection 7 to fit any of said notches. With said lug arrangedin either of said notches, the bushing will be held against rotation onthe crank 1, and to hold the lug 7 in the notch, the nut 4 is screwedtight against the bushing, longitudinal movement of the bushing beingthereby prevented. In making and assembling the parts, a clearance isprovided betweenthe end of the bushing 5 and the flange 2 so thattightening of the nut 4: causes the tapered interior of the bushing toride tightly into engagement with the taperedsurface of the crank,Whereby lost motion or relative movement of the bushing and the crank isprevented and the bushing and the crank operate substantially asintegral parts.

Where the invention press orthe like as herein illustrated, the pitman Eis provided With an eccentric strap G of the usual type, including theremovable cap H, said strap being applied to the eccentrio bushing 5 inthe usual manner of application of a strap to an ordinary eccentric.With such a construction, it will be obvious that rotation of theeccentric bushing. 5 on the crank 1 Will vary the \vorkinglength andthereby the stroke of the pitman E. In other instances of use, aneccentric embodying the invention may serve the function of changing thetime or relation of the stroke to other parts of a machine, movement ofthe bushing 5 in one direction advancing the stroke and in the otherdirection retarding the stroke.

To facilitate in adjusting the bushing 5 on the crank to vary theeccentricity, the end of the bushing adjacent the nut 4 is provided withrecesses 8 to receive a turning tool or implement. In adjusting theeccentric, the nut 4 is first loosened and the bushing 5 pushedlongitudinally to remove the lug 7 from the notch 6. This action forcesthe other end of the bushing outwardly from beneath the eccentric strapGr su flicientlyto expose the recesses 8 so that a suitable tool orimplement, such as a metal rod, may be inserted into one of therecesses, or successively into each, to turn the bushing on the crank tothe desired position. \Vith such a construction, it is unnecessary toentirely disconnect the parts of theeccentric from each other or theeccentric strap from the eccentric, and the operation of adjusting theeccentric is extremely simple.

It is to be noted that the eccentric embody ing my invention consists ofa small number of simple and comparatively inexpensive parts, whichensure strength and durability. Further, the invention avoids thenecessity for forming the drive shaft in, two parts as is common in somedevices of this character, and due to the particular construction andarrangement ofthe parts there is aminimuin tendency for the parts toWork out of adjusted relation or to unduly Wear.- v

Obviously various modifications maybe made by those skilled in the artin, carrying out my invention, without departing from the spirit andscope thereof, and I do not desirev to be understood] as limiting myselfexcept as required by the following claims is to be utilized in a Whenconstrued in the light of the prior art, v

Having thus described the invention, What I claim is 1. A shaft havingspaced journals and an eccentric portion between said journals, a pitmanon said eccentric portion, an eccentrio bushing between said eccentricportion and pitman and capable of movement both longitudinally androtatably with respect to said parts, cooperating means at one end ofsaid eccentric portion and on said bushing adapted to engage anddisengage upon longitudinal movement of said bushing in oppositedirections to hold and release said bushing respectively againstand, forrotation on said eccentric jortion, and means at the other end of theeccentric portion for releasably holding the bushing againstlongitudinal disengagement of the said cooperating means atthefirst-mentioned end of the eccentric portion and bushing'.

2. A drive shaft for presses or the like having a crank intermediate itsends, a bushing eccentri'cally mounted and capable of longitudinal androtative movement on said crank, cooperating means at one end of saidcrank and on said bushing adapted to engage and disengage uponlongitudinal movement of said bushing in opposite directions to hold andrelease said bushing respectively against and for rotation on saidcrank, the other end of said crank being tliread'ed, and a nut upon saidthreaded end of the crank to engage the adjacent end of said bushing andinfluence the bushing toward the other end of the crank.

3. A drive shaft for presses or the like having an enlarged portionintermediate its ends eccentric with respect to the axis of the shaft,all points on the periphery of said eccentric portion being outside theperipheries of the ends of the shaft, said eccentric portion beingthreaded at one end and having an annular flange at the other end formedwith circumferentia'lly spaced recesses, a nut on said threaded end, anda bushing eccen'trically mounted and capable of longitudinal androtative movement on said eccentric portion, the end of said bushingadjacent said flange having a Tag to engage any of said recesses in saidflange upon. longitudinal mo ven'ient of said bushing toward said flangeto hold said bushing against rotation.

7 4 A shaft having spaced journals and an eccentric portion. betweensaid journals tapered for part o'fits length, a pitinan on eccentricportion, an eccentric bushing between said eccentric portion and pit-manandinteriorly tapered to fit the said tapered part of the former,cooperating means on said eccentric portion and said bushing adapted toengage and disengage upon longitudinal movement of said bushing inopposite directions to hold and release said bushing respectivelyagainst and for rotation on said eccentric portion, and means on theuntapered part of the eccentric portion for engaging the adjacent end ofthe bushing and forcing it onto the tapered part.

5. A shaft having spaced journals and an eccentric portion between saidjournals tapered for part of its length, a pitnian on said eccentricportion, an eccentric bushing between said eccentric portion and pitmanand interiorly tapered to fit the said tapered part of the former,cooperating means on said eccentric portion and said bushing adapted toengage and disengage upon longitudinal movement of said bushing inopposite directions to hold and release said bushing respectivelyagainst and for rotation on said eccentric portion, and a nut on theuntapered part of the eccentric portion for engaging the adjacent end ofthe bushing and forcing it onto the tapered part.

PASQUALE BUFFARDI.

